Detergent particles comprising metal-containing bleach catalysts

ABSTRACT

The present invention relates to bleach catalyst containing composite particles suitable for incorporation into particulate detergent compositions, said composite particles comprising by weight of the particles a) from 1% to 50% of a metal containing bleach catalyst; b) from 40% to 99% of an encapsulating material; and c) from 0.5% to 20% water.

TECHNICAL FIELD

The present invention relates to bleach catalyst-containing particles,and to the preparation of these bleach catalyst-containing particles.These particles are particularly useful components of detergentcompositions, such as laundry detergent compositions, hard surfacecleaners, and especially automatic dishwashing detergent compositions.

BACKGROUND OF THE INVENTION

The use of certain bleach catalysts, particularly those comprisingcobalt or manganese compounds, in detergent compositions has beenpreviously suggested. A preferred way of incorporating such bleachcatalyst components is in small particulate form. However, the directincorporation of small bleach catalyst particles at typically very lowlevels into particulate detergent compositions can present problems.Such compositions typically, should be made up of particles having meansizes which are all similar to each other in order to avoid segregationof components in the composition. Such compositions also often compriseparticles having mean particles size in a defined range of from about400 to about 2400 microns, more usually from about 500 to about 2000microns, to achieve good flow and absence of dustiness properties. Anyfine or oversize particles outside these limits must generally beremoved by sieving to avoid a particle segregation problem. Fine bleachcatalyst particles in a detergent composition matrix may also causechemical stability problems caused by a tendency of the fine particlesto interact with other components of the overall composition, such asother bleach components.

It has now been found that the above described problems may besurprisingly ameliorated by incorporating the bleach catalyst ascomposite particles in the form of micro-encapsulates which have a sizedistribution smaller to that of the other components of the particulatedetergent composition, and which allow delivery of the bleach catalystparticle into the wash solution.

SUMMARY OF THE INVENTION

The present invention relates to bleach catalyst containing compositeparticles suitable for incorporation into particulate detergentcompositions, said composite particles comprising by weight of theparticles

a) from 1% to 50% of the metal-containing bleach catalyst;

b) from 40% to 99% of the encapsulating material; and

c) from 0.5% to 20% water.

DETAILED DESCRIPTION OF THE INVENTION

The compositions according to the present invention comprise discreteparticles of bleach catalyst and an encapsulating material. Theseparticles may optionally contain other components, such as stabilizingadditives and/or diluents. Each of these materials, the steps in thecomposite particle preparation process, the particles so prepared andparticulate detergents containing these particles are described indetail hereinafter.

Metal-containing Bleach Catalysts:

The present composite particles comprise metal-containing bleachcatalysts. Preferred are manganese and cobalt-containing bleachcatalysts.

One type of metal-containing bleach catalyst is a catalyst systemcomprising a transition metal cation of defined bleach catalyticactivity, such as copper, iron, titanium, ruthenium tungsten,molybdenum, or manganese cations, an auxiliary metal cation havinglittle or no bleach catalytic activity, such as zinc or aluminumcations, and a sequestrate having defined stability constants for thecatalytic and auxiliary metal cations, particularlyethylenediaminetetraacetic acid, (methylenephosphonic acid) andwater-soluble salts thereof. Such catalysts are disclosed in U.S. Pat.No. 4,430,243.

Other types of bleach catalysts include the manganese-based complexesdisclosed in U.S. Pat. No. 5,246,621 and U.S. Pat. No. 5,244,594.Preferred examples of these catalysts include Mn^(IV) ₂ (u-O)₃(1,4,7-trimethyl-1,4,7-triazacyclononane)₂ -(PF₆)₂ ("MnTACN"), Mn^(III)₂ (u-O)₁ (u-OAc)₂ (1,4,7-trimethyl-1,4,7-triazacyclononane)₂ -(ClO₄)₂,Mn^(IV) ₄ (u-O)₆ (1,4,7-triazacyclononane)₄ -(ClO₄)₂, Mn^(III) Mn^(IV) ₄(u-O)₁ (u-OAc)₂ -(1,4,7-trimethyl-1,4,7-triazacyclononane)₂ -(ClO₄)₃,and mixtures thereof. See also European patent application publicationno. 549,272. Other ligands suitable for use herein include1,5,9-trimethyl-1,5,9-triazacyclododecane,2-methyl-1,4,7-triazacyclononane, 2-methyl-1,4,7-triazacyclononane, andmixtures thereof.

Bleach catalysts of particular use in automatic dishwashing compositionsand concentrated powder detergent compositions may also be selected asappropriate for the present invention. For examples of suitable bleachcatalysts see U.S. Pat. No. 4,246,612 and U.S. Pat. No. 5,227,084.

See also U.S. Pat. No. 5,194,416 which teaches mononuclear manganese(IV) complexes such as Mn(1,4,7-trimethyl-1,4,7-triazacyclononane(OCH₃)₃-(PF₆).

Still another type of bleach catalyst, as disclosed in U.S. Pat. No.5,114,606, is a water-soluble complex of manganese (II), (III), and/or(IV) with a ligand which is a non-carboxylate polyhydroxy compoundhaving at least three consecutive C--OH groups. Preferred ligandsinclude sorbitol, iditol, dulsitol, mannitol, xylitol, arabitol,adonitol, meso-erythritol, meso-inositol, lactose, and mixtures thereof.

U.S. Pat. No. 5,114,611 teaches a bleach catalyst comprising a complexof transition metals, including Mn, Co, Fe, or Cu, with annon-(macro)-cyclic ligand. Said ligands are of the formula: ##STR1##wherein R¹, R², R³, and R⁴ can each be selected from H, substitutedalkyl and aryl groups such that each R¹ --N═C--R² and R³ --C═N--R⁴ forma five or six-membered ring. Said ring can further be substituted. B isa bridging group selected from O, S. CR⁵ R⁶, NR⁷ and C═O, wherein R⁵,R⁶, and R⁷ can each be H, alkyl, or aryl groups, including substitutedor unsubstituted groups. Preferred ligands include pyridine, pyridazine,pyrimidine, pyrazine, imidazole, pyrazole, and triazole rings.Optionally, said rings may be substituted with substituents such asalkyl, aryl, alkoxy, halide, and nitro. Particularly preferred is theligand 2,2'-bispyridylamine. Preferred bleach catalysts include Co, Cu,Mn, Fe, -bispyridylmethane and -bispyridylamine complexes. Highlypreferred catalysts include Co(2,2'-bispyridylamine)Cl₂,Di(isothiocyanato)bispyridylamine-cobalt (II),trisdipyridylamine-cobalt(II) perchlorate, Co(2,2-bispyridylamine)₂ O₂ClO₄, Bis-(2,2'-bispyridylamine) copper(II) perchlorate,tris(di-2-pyridylamine) iron(II) perchlorate, and mixtures thereof.

Other examples include Mn gluconate, Mn(CF₃ SO₃)₂, Co(NH₃)₅ Cl, and thebinuclear Mn complexed with tetra-N-dentate and bi-N-dentate ligands,including N₄ Mn^(III) (u-O)₂ Mn^(IV) N₄)⁺ and [Bipy₂ Mn^(III) (u-O)₂Mn^(IV) bipy₂ ]-(ClO₄)₃.

The bleach catalysts may also be prepared by combining a water-solubleligand with a water-soluble manganese salt in aqueous media andconcentrating the resulting mixture by evaporation. Any convenientwater-soluble salt of manganese can be used herein. Manganese (II),(III), (IV) and/or (V) is readily available on a commercial scale.

Other bleach catalysts are described, for example, in European patentapplication, publication no. 408,131 (cobalt complex catalysts),European patent applications, publication nos. 384,503, and 306,089(metallo-porphyrin catalysts), U.S. Pat. No. 4,728,455(manganese/multidentate ligand catalyst), U.S. Pat. No. 4,711,748 andEuropean patent application, publication no. 224,952, (absorbedmanganese on aluminosilicate catalyst), U.S. Pat. No. 4,601,845(aluminosilicate support with manganese and zinc or magnesium salt),U.S. Pat. No. 4,626,373 (manganese/ligand catalyst), U.S. Pat. No.4,119,557 (ferric complex catalyst), German Pat. specification 2,054,019(cobalt chelant catalyst) Canadian 866,191 (transition metal-containingsalts), U.S. Pat. No. 4,430,243 (chelants with manganese cations andnon-catalytic metal cations), and U.S. Pat. No. 4,728,455 (manganesegluconate catalysts).

Preferred are cobalt (III) catalysts having the formula:

    Co[(NH.sub.3).sub.n M'.sub.m B'.sub.b T'.sub.t Q.sub.q P.sub.p ]Y.sub.y

wherein cobalt is in the +3 oxidation state; n is an integer from 0 to 5(preferably 4 or 5; most preferably 5); M' represents a monodentateligand; m is an integer from 0 to 5 (preferably 1 or 2; most preferably1); B' represents a bidentate ligand; b is an integer from 0 to 2; T'represents a tridentate ligand; t is 0 or 1; Q is a tetradentate ligand;q is 0 or 1; P is a pentadentate ligand; p is 0 or 1; andn+m+2b+3t+4q+5p=6; Y is one or more appropriately selected counteranionspresent in a number y, where y is an integer from 1 to 3 (preferably 2to 3; most preferably 2 when Y is a -1 charged anion), to obtain acharge-balanced salt, preferred Y are selected from the group consistingof chloride, nitrate, nitrite, sulfate, citrate, acetate, carbonate, andcombinations thereof; and wherein further at least one of thecoordination sites attached to the cobalt is labile under automaticdishwashing use conditions and the remaining coordination sitesstabilize the cobalt under automatic dishwashing conditions such thatthe reduction potential for cobalt (III) to cobalt (II) under alkalineconditions is less than about 0.4 volts (preferably less than about 0.2volts) versus a normal hydrogen electrode.

Preferred cobalt catalysts of this type have the formula:

    [Co(NH.sub.3).sub.n (M').sub.m ]Y.sub.y

wherein n is an integer from 3 to 5 (preferably 4 or 5; most preferably5); M' is a labile coordinating moiety, preferably selected from thegroup consisting of chlorine, bromine, hydroxide, water, and (when m isgreater than 1) combinations thereof; m is an integer from 1 to 3(preferably 1 or 2; most preferably 1); m+n=6; and Y is an appropriatelyselected counteranion present in a number y, which is an integer from 1to 3 (preferably 2 to 3; most preferably 2 when Y is a -1 chargedanion), to obtain a charge-balanced salt.

The preferred cobalt catalyst of this type useful herein are cobaltpentaamine chloride salts having the formula [Co(NH₃)₅ Cl]Y_(y), andespecially [Co(NH₃)₅ Cl]Cl₂.

More preferred are the present invention compositions which utilizecobalt (III) bleach catalysts having the formula:

    [Co(NH.sub.3).sub.n (M).sub.m (B).sub.b ]T.sub.y

wherein cobalt is in the +3 oxidation state; n is 4 or 5 (preferably 5);M is one or more ligands coordinated to the cobalt by one site; m is 0,1 or 2 (preferably 1); B is a ligand coordinated to the cobalt by twosites; b is 0 or 1 (preferably 0), and when b=0, then m+n=6, and whenb=1, then m=0 and n=4; and T is one or more appropriately selectedcounteranions present in a number y, where y is an integer to obtain acharge-balanced salt (preferably y is 1 to 3; most preferably 2 when Tis a -1 charged anion); and wherein further said catalyst has a basehydrolysis rate constant of less than 0.23 M⁻¹ s⁻¹ (25° C.).

Preferred T are selected from the group consisting of chloride, iodide,I₃ ⁻, formate, nitrate, nitrite, sulfate, sulfite, citrate, acetate,carbonate, bromide, PF₆ ⁻, BF₄ ⁻, B(Ph)₄ ⁻, phosphate, phosphite,silicate, tosylate, methanesulfonate, and combinations thereof.Optionally, T can be protonated if more than one anionic group exists inT, e.g., HPO₄ ²⁻, HCO₃ ⁻, H₂ PO₄ ⁻, etc. Further, T may be selected fromthe group consisting of non-traditional inorganic anions such as anionicsurfactants (e.g., linear alkylbenzene sulfonates (LAS), alkyl sulfates(AS), alkylethoxysulfonates (AES), etc.) and/or anionic polymers (e.g.,polyacrylates, polymethacrylates, etc.).

The M moieties include, but are not limited to, for example, F⁻, SO₄ ⁻²,NCS⁻, SCN⁻, S₂ O₃ ⁻², NH₃, PO₄ ³⁻, and carboxylates (which preferablyare mono-carboxylates, but more than one carboxylate may be present inthe moiety as long as the binding to the cobalt is by only onecarboxylate per moiety, in which case the other carboxylate in the Mmoiety may be protonated or in its salt form). Optionally, M can beprotonated if more than one anionic group exists in M (e.g., HPO₄ ²⁻,HCO₃ ⁻, H₂ PO₄ ⁻, HOC(O)CH₂ C(O)O--, etc.) Preferred M moieties aresubstituted and unsubstituted C₁ -C₃₀ carboxylic acids having theformulas:

    RC(O)O--

wherein R is preferably selected from the group consisting of hydrogenand C₁ -C₃₀ (preferably C₁ -C₁₈) unsubstituted and substituted alkyl, C₆-C₃₀ (preferably C₆ -C₁₈) unsubstituted and substituted aryl, and C₃-C₃₀ (preferably C₅ -C₁₈) unsubstituted and substituted heteroaryl,wherein substituents are selected from the group consisting of --NR'₃,--NR'₄ ⁺, --C(O)OR', --OR', --C(O)NR'₂, wherein R' is selected from thegroup consisting of hydrogen and C₁ -C₆ moieties. Such substituted Rtherefore include the moieties --(CH₂)_(n) OH and --(CH₂)_(n) NR'₄ ⁺,wherein n is an integer from 1 to about 16, preferably from about 2 toabout 10. and most preferably from about 2 to about 5.

Most preferred M are carboxylic acids having the formula above wherein Ris selected from the group consisting of hydrogen, methyl, ethyl,propyl, straight or branched C₄ -C₁₂ alkyl, and benzyl. Most preferred Ris methyl. Preferred carboxylic acid M moieties include formic, benzoic,octanoic, nonanoic, decanoic, dodecanoic, malonic, maleic, succinic,adipic, phthalic, 2-ethylhexanoic, naphthenoic, oleic, palmitic,triflate, tartrate, stearic, butyric, citric, acrylic, aspartic,fumaric, lauric, linoleic, lactic, malic, and especially acetic acid.

The B moieties include carbonate, di- and higher carboxylates (e.g.,oxalate, malonate, malic, succinate, maleate), picolinic acid, and alphaand beta amino acids (e.g., glycine, alanine, beta-alanine,phenylalanine).

Cobalt bleach catalysts useful herein are known, being described forexample along with their base hydrolysis rates, in M. L. Tobe, "BaseHydrolysis of Transition-Metal Complexes", Adv. Inorg. Bioinorg. Mech.,(1983), 2, pages 1-94. For example, Table 1 at page 17, provides thebase hydrolysis rates (designated therein as k_(OH)) for cobaltpentaamine catalysts complexed with oxalate (k_(OH) =2.5×10⁻⁴ M⁻¹ s⁻¹(25° C.)), NCS⁻ (k_(OH) =5.0×10⁻⁴ M⁻¹ s⁻¹ (25° C.)), formate (k_(OH)=5.8×10⁻⁴ M⁻¹ s⁻¹ (25° C.)), and acetate (k_(OH) =9.6×10⁻⁴ M⁻¹ s⁻¹ (25°C.)). The most preferred cobalt catalyst useful herein are cobaltpentaamine acetate salts having the formula [Co(NH₃)₅ OAc] T_(y),wherein OAc represents an acetate moiety, and especially cobaltpentaamine acetate chloride, [Co(NH₃)₅ OAc]Cl_(2;) as well as [Co(NH₃)₅OAc](OAc)2; [Co(NH₃)₅ OAc](PF₆)₂ ; [Co(NH₃)₅ OAc](SO₄); [Co(NH₃)₅OAc](BF₄)₂ ; and [Co(NH₃)₅ OAc](NO₃)2 (herein "PAC").

These cobalt catalysts are readily prepared by known procedures, such astaught for example in the Tobe article hereinbefore and the referencescited therein, in U.S. Pat. No. 4,810,410, to Diakun et al, issued Mar.7, 1989, J. Chem. Ed. (1989), 66 (12), 1043-45; The Synthesis andCharacterization of Inorganic Compounds, W. L. Jolly (Prentice-Hall;1970), pp. 461-3; Inorg. Chem., 18, 1497-1502 (1979); Inorg. Chem., 21,2881-2885 (1982); Inorg. Chem., 18, 2023-2025 (1979); Inorg. Synthesis,173-176 (1960); and Journal of Physical Chemistry, 56, 22-25 (1952); aswell as the synthesis examples provided hereinafter.

The bleach catalyst-containing composite particles of the inventioncomprise from 1 to 50%, preferably from 2% to 30%, most preferably from3% to 25% by weight of the metal-containing bleach catalyst.

As a practical matter, and not by way of limitation, the cleaningcompositions and cleaning processes herein can be adjusted to provide onthe order of at least one part per hundred million of the active bleachcatalyst species in the aqueous washing medium, and will preferablyprovide from about 0.01 ppm to about 25 ppm, more preferably from about0.05 ppm to about 10 ppm, and most preferably from about 0.1 ppm toabout 5 ppm, of the bleach catalyst species in the wash liquor. In orderto obtain such levels in the wash liquor of an automatic dishwashingprocess, typical automatic dishwashing compositions herein will comprisefrom about 0.0005% to about 0.2%, more preferably from about 0.004% toabout 0.08%, of bleach catalyst by weight of the cleaning compositions.

Micro-encapsulates

The bleach catalyst-containing composite particles are comprised of from40% to 99% by weight, preferably 50% to 98% by weight, most preferably60% to 97% by weight encapsulating material.

The encapsulating material should be inert to reaction with the bleachcatalyst component of the particle under processing conditions and aftersolidification. Furthermore the encapsulating material is preferablywater-soluble. Additionally, the encapsulating material should besubstantially free of moisture present as unbound water.

Examples of suitable encapsulating materials include gelatine,hydrolyzed gelatine, film forming carbohydrates. Preferred encapsulatingmaterials are low-bloom gelatin, hydrolyzed gelatine, and film-formingcarbohydrates including dextrin and gum Arabic.

The metal-containing bleach catalyst encapsulated composition describedabove can be prepared by a method comprising:

(1) dissolving the metal-containing bleach catalyst in an aqueousmedium,

(2) mixing the metal-containing bleach catalyst solution with an aqueoussolution of the encapsulating material,

(3) converting the mixture thus obtained into droplets of an averageparticle size not exceeding 450 micrometer and

(4) reducing the moisture content of said particles to a value ofbetween 0.5% and 20% by weight to form a solid solution of themetal-containing bleach catalyst in the encapsulating material.

The encapsulating material should preferably have a molecular weightwhich is substantially higher than that of the metal-containing bleachcatalyst. Thus, if the size of the molecules of the metal-containingbleach catalyst is less than about 0.6 of that of the encapsulatingmaterial, an extensive interstitial solid solution i.e. a solid solutionin which the solute molecules occupy the interstitial space of thesolvent lattice is obtained.

The conversion of the mixture into droplets and the reduction of themoisture content of the droplets are preferably effected by aspray-drying technique.

In a preferred embodiment of the method of the invention the mixture isspray-dried at an elevated temperature of below 100° C. whileintroducing a fine powder into the spray drying zone, as explained in USpatent specification no. 2,756,177. The fine powder can be silicate orfinely divided corn starch, preferably finely divided corn starch.

In another preferred embodiment the mixture is spray-dried at atemperature of above 100° C.

In a preferred embodiment, sugar (saccharose) or glucose syrup can beadded to the mixture to be spray-dried in order to lower the viscosityof the mixture, the weight ratio of encapsulating material to sugarbeing at least 35:65, preferably 50:50.

Preferably an oil such as coconut oil is incorporated in the mixture tobe spray-dried in the form of an emulsion. The presence of the oilfacilitates the formation of droplets when the mixture is spray-dried,and amounts of from 2% to 20% by weight, preferably 3% to 10% by weightare used. The most preferred amount of oil is 5% by weight.

The dry matter content of the mixture to be spray-dried may vary withinwide ranges but the viscosity is preferably maintained within the rangeof from 70 cp to 200 cp at 60° C.

Preferably, the composite particles herein have a particle size of from10 to 450 micrometers.

Compositions, including detergent compositions herein, preferablycontain composite particles having a particle size distribution suchthat at least 50% by weight of the particles have a particle size in therange of from 10 to 450 micrometers.

Detergent Compositions

The micro-encapsulated particles herein are useful components ofdetergent compositions, particularly those designed for use in automaticdishwashing methods.

Detergent compositions according to the invention preferably containsthe bleach catalyst composition described above in an amount of from 2ppm to 1,000 ppm preferably from 10 ppm to 100 ppm by weight ofdetergent composition of the pure bleach catalyst by weight of thedetergent composition.

The detergent composition may additionally contain detergent ingredientse.g. builder components, other bleaches, bleach activators, silicates,dispersant polymers, surfactants, enzyme stabilizers, suds suppressors,corrosion inhibitors, fillers, hydrotropes and perfumes.

A preferred granular or powdered detergent composition comprises byweight:

(a) from about 0.1% to about 10% of the bleach catalyst compositeparticles as hereinbefore described;

(b) a bleach component comprising from about 0.01% to about 8% (asavailable oxygen "AvO") of a peroxygen bleach;

(c) from about 0.1% to about 90% of a pH adjusting component consistingof water-soluble salt, builder or salt/builder mixture selected from thegroup consisting of the alkali and alkaline earth metal phosphates,carbonates, sesquicarbonates, citrates, bicarbonates, and hydroxides,citric acid and mixtures thereof;

(d) from about 3% to about 20% silicate (as SiO₂);

(e) from 0% to about 10% of a low-foaming nonionic surfactant,especially other than an amine oxide;

(f) from 0% to about 10% of a suds suppressor;

(g) from 0% to about 25% of a dispersant polymer.

Such compositions are typically formulated to provide an in-use washsolution pH from about 9.5 to about 11.5.

Bleaches

The fully-formulated detergent compositions herein preferably contain anoxygen bleaching source. Oxygen bleach is employed in an amountsufficient to provide from 0.01% to about 8%, preferably from about 0.1%to about 5.0%, more preferably from about 0.3% to about 4.0%, mostpreferably from about 0.5% to about 3% of available oxygen (AvO) byweight of the detergent composition.

Available oxygen of a detergent composition or a bleach component is theequivalent bleaching oxygen content thereof expressed as % oxygen. Forexample, commercially available sodium perborate monohydrate typicallyhas an available oxygen content for bleaching purposes of about 15%(theory predicts a maximum of about 16%). Methods for determiningavailable oxygen of a formula after manufacture share similar chemicalprinciples but depend on whether the oxygen bleach incorporated thereinis a simple hydrogen peroxide source such as sodium perborate orpercarbonate, is an activated type (e.g., perborate with tetra-acetylethylenediamine) or comprises a performed peracid such asmonoperphthalic acid. Analysis of peroxygen compounds is well-known inthe art: see, for example, the publications of Swern, such as "OrganicPeroxides", Vol. I, D. H. Swern, Editor; Wiley, New York, 1970, LC #72-84965, incorporated by reference. See for example the calculation of"percent active oxygen" at page 499. This term is equivalent to theterms "available oxygen" or "percent available oxygen" as used herein.

The peroxygen bleaching systems useful herein are those capable ofyielding hydrogen peroxide in an aqueous liquor. These compounds includebut are not limited to the alkali metal peroxides, organic peroxidebleaching compounds such as urea peroxide and inorganic persaltbleaching compounds such as the alkali metal perborates, percarbonates,perphosphates, and the like. Mixtures of two or more such bleachingcompounds can also be used.

Preferred peroxygen bleaching compounds include sodium perborate,commercially available in the form of mono-, tri-, and tetra-hydrate,sodium pyrophosphate peroxyhydrate, urea peroxyhydrate, sodiumpercarbonate, and sodium peroxide. Particularly preferred are sodiumperborate tetrahydrate, sodium perborate monohydrate and sodiumpercarbonate.

Suitable oxygen-type bleaches are further described in U.S. Pat. No.4,412,934 (Chung et al), issued Nov. 1, 1983, and peroxyacid bleachesdescribed in European Patent Application 033,259. Sagel et al, publishedSep. 13, 1989, both incorporated herein by reference, can be used.

Highly preferred percarbonate can be in uncoated or coated form. Theaverage particle size of uncoated percarbonate ranges from about 400 toabout 1200 microns, most preferably from about 400 to about 600 microns.If coated percarbonate is used, the preferred coating materials includecarbonate, sulfate, silicate, borosilicate, fatty carboxylic acids, andmixtures thereof.

Preferably, the peroxygen bleach component in the composition isformulated with an activator (peracid precursor). The activator ispresent at levels of from about 0.01% to about 15%, preferably fromabout 1% to about 10%, more preferably from about 1% to about 8%, byweight of the composition. Preferred activators are selected from thegroup consisting of tetraacetyl ethylene diamin (TAED),benzoylcaprolactam (BzCL), 4-nitrobenzoylcaprolactam,3-chlorobenzoylcaprolactam, benzoyloxybenzenesulphonate (BOBS),nonanoyloxybenzenesulphonate (NOBS), phenyl benzoate (PhBz),decanoyloxybenzenesulphonate (C₁₀ -OBS), benzoylvalerolactam (BZVL),octanoyloxybenzenesulphonate (C₈ -OBS), perhydrolyzable esters andmixtures thereof, most preferably benzoylcaprolactam andbenzoylvalerolactam. Particularly preferred bleach activators in the pHrange from about 8 to about 9.5 are those selected having an OBS or VLleaving group.

Preferred bleach activators are those described in U.S. Pat. No.5,130,045, Mitchell et al, and U.S. Pat. No. 4,412,934, Chung et al, andcopending patent applications U.S. Ser. Nos. 08/064,624, 08/064,623,08/064,621, 08/064,562, 08/064,564, 08/082,270 and copending applicationto M. Burns, A. D. Willey, R. T. Hartshorn, C. K. Ghosh, entitled"Bleaching Compounds Comprising Peroxyacid Activators Used With Enzymes"and having U.S. Ser. No. 08/133,691 (P&G Case 4890R), all of which areincorporated herein by reference.

The mole ratio of peroxygen bleaching compound (as AvO) to bleachactivator in the present invention generally ranges from at least 1:1,preferably from about 20:1 to about 1:1, more prefer ably from about10:1 to about 3:11.

Quaternary substituted bleach activators may also be included. Thepresent detergent compositions comprise a quaternary substituted bleachactivator (QSBA) or a quaternary substituted peracid (QSP); morepreferably, the former. Preferred QSBA structures are further describedin copending U.S. Ser. No. 08/298,903, 08/298,650, 08/298,906 and08/298,904 filed Aug. 31, 1994, incorporated herein by reference.

Diacyl Peroxide Bleaching Species

The compositions in accordance with the present invention may alsocomprise a diacylperoxide bleach. The diacyl peroxides are addedseparately to the compositions at levels from about 0.01% to about 15%The individual diacyl peroxide particles used herein preferably have amean particle size of less than about 300 microns, preferably less thanabout 200 microns, more preferably from about 1 to about 150 microns,most preferably from about 10 to about 100 microns.

The diacyl peroxide is preferably a diacyl peroxide of the generalformula:

    RC(O)OO(O)CR.sup.1

wherein R and R¹ can be the same or different, and each comprises ahydrocarbyl group containing more than ten carbon atoms. Preferably, atleast one of these groups has an aromatic nucleus.

Examples of suitable diacyl peroxides are those selected from the groupconsisting of dibenzoyl peroxide ("benzoyl peroxide"), benzoyl glutarylperoxide, benzoyl succinyl peroxide, di-(2-methybenzoyl) peroxide,diphthaloyl peroxide an d mixtures thereof, more preferably dibenzoylperoxide, diphthaloyl peroxides and mixtures thereof. The preferreddiacyl peroxide is dibenzoyl peroxide.

The diacyl peroxide thermally decomposes under wash conditions (i.e.typically from about 38° C. to about 71° C.) to form free radicals. Thisoccurs even when the diacyl peroxide particles are water-insoluble.

Surprisingly, particle size can play an important role in theperformance of the diacyl peroxide, not only in preventing residuedeposit problems, but also in enhancing the removal of stains,particularly from stained plasticware. The mean particle size of thediacyl peroxide particles produced in wash solution after dissolution oft he particle composite carrier material, as measured by a laserparticle size analyzer (e.g. Malvern) on an agitated mixture with waterof the diacyl peroxide, is less than about 300 microns, preferably lessthan about 200 microns. Although water insolubility is an essentialcharacteristic of the diacyl peroxide used in the present invention, thesize of the particles containing it is also important for controllingresidue formation in the wash and maximizing stain removal performance.

Preferred diacyl peroxides used in the present compositions are alsoformulated into a carrier material that melts within the range of fromabout 38° C. to about 77° C., preferably selected from the groupconsisting of polyethylene glycols, paraffin waxes, and mixturesthereof, as taught in copending U.S. patent application Ser. No.08/424,132, filed Apr. 17, 1995.

pH-Adjusting Control/Detergency Builder Components

The detergent compositions herein will preferably provide wash solutionshaving a pH of at least 7; therefore the compositions will typicallycomprise a pH-adjusting detergency builder component selected fromwater-soluble alkaline inorganic salts and water-soluble organic orinorganic builders. A wash solution pH of from 7 to about 13, preferablyfrom about 8 to about 12, more preferably from about 8 to about 11.0 isdesirable. The pH-adjusting components are selected so that when thedetergent composition is dissolved in water at a concentration of2000-6000 ppm, the pH remains in the ranges discussed above. Thepreferred non phosphate pH-adjusting component embodiments of theinvention is selected from the group consisting of:

(i) sodium/potassium carbonate or sesquicarbonate

(ii) sodium/potassium citrate

(iii) citric acid

(iv) sodium/potassium bicarbonate

(v) sodium/potassium borate, preferably borax

(vi) sodium/potassium hydroxide;

(vii) sodium/potassium silicate and

(viii) mixtures of (i)-(vii).

Illustrative of highly preferred pH-adjusting component systems arebinary mixtures of granular sodium citrate dihydrate with anhydroussodium carbonate, and three-component mixtures of granular sodiumcitrate dihydrate, sodium carbonate and sodium disilicate.

The amount of the pH adjusting component included in the detergentcompositions is generally from about 0.9% to about 99%, preferably fromabout 5% to about 70%, more preferably from about 20% to about 60% byweight of the composition.

Any pH-adjusting system can be complemented (i.e. for improvedsequestration in hard water) by other optional detergency builder saltsselected from phosphate or nonphosphate detergency builders known in theart, which include the various water-soluble, alkali metal, ammonium orsubstituted ammonium borates, hydroxysulfonates, polyacetates, andpolycarboxylates. Preferred are the alkali metal, especially sodium,salts of such materials. Alternate water-soluble, non-phosphorus organicbuilders can be used for their sequestering properties. Examples ofpolyacetate and polycarboxylate builders are the sodium, potassium,lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, ethylenediamine disuccinic acid (especially theS,S-form); nitrilotriacetic acid, tartrate monosuccinic acid, tartratedisuccinic acid, oxydiacetic acid, oxydisuccinic acid,carboxymethyloxysuccinic acid, mellitic acid, and sodium benzenepolycarboxylate salts.

The detergency builders can be any of the detergency builders known inthe art, which include the various water-soluble, alkali metal, ammoniumor substituted ammonium phosphates, polyphosphates, phosphonates,polyphosphonates, carbonates, borates, polyhydroxysulfonates,polyacetates, carboxylates (e.g. citrates), aluminosilicates andpolycarboxylates. Preferred are the alkali metal, especially sodium,salts of the above and mixtures thereof.

Specific examples of inorganic phosphate detergency builders which alsoserve to adjust pH are sodium ("STPP") and potassium tripolyphosphates,pyrophosphate, polymeric metaphosphate having a degree of polymerizationof from about 6 to 21, and orthophosphate. Examples of polyphosphonatebuilders are the sodium and potassium salts of ethylene diphosphonicacid, the sodium and potassium salts of ethane 1-hydroxy-1,1-diphosphonic acid and the sodium and potassium salts of ethane,1,1,2-triphosphonic acid. Other phosphorus builder compounds aredisclosed in U.S. Pat. Nos. 3,159,581; 3,213,030; 3,422,021; 3,422,137,3,400,176 and 3,400,148, incorporated herein by reference.

Non-phosphate detergency builders include but are not limited to thevarious water-soluble, alkali metal, ammonium or substituted ammoniumborates, hydroxysulfonates, polyacetates, and polycarboxylates.Preferred are the alkali metal, especially sodium, salts of suchmaterials. Alternate water-soluble, non-phosphorus organic builders canbe used for their sequestering properties. Examples of polyacetate andpolycarboxylate builders are the sodium, potassium, lithium, ammoniumand substituted ammonium salts of ethylenediamine tetraacetic acid,ethylenediamine disuccinic acid (especially the S,S-form);nitrilotriacetic acid, tartrate monosuccinic acid, tartrate disuccinicacid, oxydisuccinic acid, carboxymethyloxysuccinic acid, mellitic acid,and sodium benzene polycarboxylate salts.

In general, the pH values of the detergent compositions can vary duringthe course of the wash as a result of the water and soil present. Thebest procedure for determining whether a given composition has theherein-indicated pH values is as follows: prepare an aqueous solution ordispersion of all the ingredients of the composition by mixing them infinely divided form with the required amount of water to have a 3000 ppmtotal concentration. Measure the pH using a conventional glass electrodeat ambient temperature, within about 2 minutes of forming the solutionor dispersion. To be clear, this procedure relates to pH measurement andis not intended to be construed as limiting of the detergentcompositions in any way; for example, it is clearly envisaged thatfully-formulated embodiments of the instant detergent compositions maycomprise a variety of ingredients applied as coatings to otheringredients.

Silicates

The compositions of the type described herein optionally, but preferablycomprise alkali metal silicates and/or metasilicates. The alkali metalsilicates hereinafter described provide pH adjusting capability (asdescribed above), protection against corrosion of metals and againstattack on dishware, inhibition of corrosion to glasswares andchinawares. The SiO₂ level is from about 0.5% to about 20%, preferablyfrom about 1% to about 15%, more preferably from about 2% to about 12%,most preferably from about 3% to about 10%, based on the weight of thedetergent composition.

The ratio of SiO₂ to the alkali metal oxide (M₂ O, where M=alkali metal)is typically from about 1 to about 3.2, preferably from about 1 to about3, more preferably from about 1 to about 2.4. Preferably, the alkalimetal silicate is hydrous, having from about 15% to about 25% water,more preferably, from about 17% to about 20%. Metasilicate having anSiO₂ :M₂ O ratio of about 1:1 is also useful.

Anhydrous forms of the alkali metal silicates with a SiO₂ :M₂ O ratio of2.0 or more are also less preferred because they tend to besignificantly less soluble than the hydrous alkali metal silicateshaving the same ratio. Sodium and potassium, and especially sodium,silicates are preferred. A particularly preferred alkali metal silicateis a granular hydrous sodium silicate having a SiO₂ :Na₂ O ratio of from2.0 to 2.4 available from PQ Corporation, named Britesil H20 andBritesil H24. Most preferred is a granular hydrous sodium silicatehaving a SiO₂ :Na₂ O ratio of 2.0. While typical forms, i.e. powder andgranular, of hydrous silicate particles are suitable, preferred silicateparticles have a mean particle size between about 300 and about 900microns with less than 40% smaller than 150 microns and less than 5%larger than 1700 microns. Particularly preferred is a silicate particlewith a mean particle size between about 400 and about 700 microns withless than 20% smaller than 150 microns and less than 1% larger than 1700microns.

Other suitable silicates include the crystalline layered sodiumsilicates have the general formula:

    NaMSi.sub.x O.sub.2x+1.y H.sub.2 O

wherein M is sodium or hydrogen, x is a number from 1.9 to 4 and y is anumber from 0 to 20. Crystalline layered sodium silicates of this typeare disclosed in EP-A-0164514 and methods for their preparation aredisclosed in DE-A-3417649 and DE-A-3742043. For the purpose of thepresent invention, x in the general formula above has a value of 2, 3 or4. The most preferred material is δ-Na₂ Si₂ O₅, available from HoechstAG as NaSKS-6.

The crystalline layered sodium silicate material is preferably presentin granular detergent compositions as a particle in intimate admixturewith a solid, water-soluble ionisable material. The solid, water-solubleionisable material is selected from organic acids, organic and inorganicacid salts and mixtures thereof.

Low-Foaming Nonionic Surfactant

Detergent compositions of the present invention can comprise low foamingnonionic surfactants (LFNIs). LFNI can be present in amounts from 0 toabout 10% by weight, preferably from about 1% to about 8%. morepreferably from about 0.25% to about 4%. LFNIs are most typically usedin detergent compositions on account of the improved water-sheetingaction (especially from glass) which they confer to the detergentcomposition product. They also encompass non-silicone, nonphosphatepolymeric materials further illustrated hereinafter which are known todefoam food soils encountered in automatic dishwashing.

Preferred LFNIs include nonionic alkoxylated surfactants, especiallyethoxylates derived from primary alcohols, and blends thereof with moresophisticated surfactants, such as thepolyoxypropylene/polyoxyethylene/polyoxypropylene reverse blockpolymers. The PO/EO/PO polymer-type surfactants are well-known to havefoam suppressing or defoaming action, especially in relation to commonfood soil ingredients such as egg.

The invention encompasses preferred embodiments wherein LFNI is present,and wherein this component is solid at temperatures below about 100° F.,more preferably below about 120° F.

In a preferred embodiment, the LFNI is an ethoxylated surfactant derivedfrom the reaction of a monohydroxy alcohol or alkylphenol containingfrom about 8 to about 20 carbon atoms, excluding cyclic carbon atoms,with from about 6 to about 15 moles of ethylene oxide per mole ofalcohol or alkyl phenol on an average basis.

A particularly preferred LFNI is derived from a straight chain fattyalcohol containing from about 16 to about 20 carbon atoms (C₁₆ -C₂₀alcohol), preferably a C₁₈ alcohol, condensed with an average of fromabout 6 to about 15 moles, preferably from about 7 to about 12 moles,and most preferably from about 7 to about 9 moles of ethylene oxide permole of alcohol. Preferably the ethoxylated nonionic surfactant soderived has a narrow ethoxylate distribution relative to the average.

The LFNI can optionally contain propylene oxide in an amount up to about15% by weight. Other preferred LFNI surfactants can be prepared by theprocesses described in U.S. Pat. No. 4,223,163, issued Sep. 16, 1980,Builloty, incorporated herein by reference.

Highly preferred detergent compositions herein wherein the LFNI ispresent make use of ethoxylated monohydroxy alcohol or alkyl phenol andadditionally comprise a polyoxyethylene, polyoxypropylene blockpolymeric compound; the ethoxylated monohydroxy alcohol or alkyl phenolfraction of the LFNI comprising from about 20% to about 80%, preferablyfrom about 30% to about 70%, of the total LFNI.

Suitable block polyoxyethylene-polyoxypropylene polymeric compounds thatmeet the requirements described herein before include those based onethylene glycol, propylene glycol, glycerol, trimethylolpropane andethylenediamine as initiator reactive hydrogen compound. Polymericcompounds made from a sequential ethoxylation and propoxylation ofinitiator compounds with a single reactive hydrogen atom, such as C₁₂₋₁₈aliphatic alcohols, do not generally provide satisfactory suds controlin the instant detergent compositions. Certain of the block polymersurfactant compounds designated PLURONIC® and TETRONIC® by theBASF-Wyandotte Corp., Wyandotte, Mich., are suitable in detergentcomposition compositions herein.

A particularly preferred LFNI contains from about 40% to about 70% of apolyoxypropylene/polyoxyethylene/polyoxypropylene block polymer blendcomprising about 75%, by weight of the blend, of a reverse blockco-polymer of polyoxyethylene and polyoxypropylene containing 17 molesof ethylene oxide and 44 moles of propylene oxide; and about 25%, byweight of the blend, of a block co-polymer of polyoxyethylene andpolyoxypropylene initiated with trimethylolpropane and containing 99moles of propylene oxide and 24 moles of ethylene oxide per mole oftrimethylolpropane.

Suitable for use as LFNI in the detergent composition compositions arethose LFNI having relatively low cloud points and highhydrophilic-lipophilic balance (HLB). Cloud points of 1% solutions inwater are typically below about 32° C. and preferably lower, e.g., 0°C., for optimum control of sudsing throughout a full range of watertemperatures.

LFNIs which may also be used include a C₁₈ alcohol polyethoxylate,having a degree of ethoxylation of about 8, commercially available SLF18from Olin Corp. and any biodegradable LFNI having the melting pointproperties discussed herein above.

Anionic Co-surfactant

The automatic dishwashing detergent compositions herein can additionallycontain an anionic co-surfactant. When present, the anionicco-surfactant is typically in an amount from 0% to about 10%, preferablyfrom about 0.1% to about 8%, more preferably from about 0.5% to about5%, by weight of the detergent composition.

Suitable anionic co-surfactants include branched or linear alkylsulfates and sulfonates. These may contain from about 8 to about 20carbon atoms. Other anionic cosurfactants include the alkyl benzenesulfonates containing from about 6 to about 13 carbon atoms in the alkylgroup, and mono- and/or dialkyl phenyl oxide mono- and/or di-sulfonateswherein the alkyl groups contain from about 6 to about 16 carbon atoms.All of these anionic co-surfactants are used as stable salts, preferablysodium and/or potassium.

Preferred anionic co-surfactants include sulfobetaines, betaines,alkyl(polyethoxy)sulfates (AES) and alkyl (polyethoxy)carboxylates whichare usually high sudsing. Optional anionic co-surfactants are furtherillustrated in published British Patent Application No. 2,116,199A; U.S.Pat. No. 4,005,027, Hartman; U.S. Pat. No. 4,116,851, Rupe et al; andU.S. Pat. No. 4,116,849, Leikhim, all of which are incorporated hereinby reference.

Preferred alkyl(polyethoxy)-sulfate surfactants comprise a primary alkylethoxy sulfate derived from the condensation product of a C₆ -C₁₈alcohol with an average of from about 0.5 to about 20, preferably fromabout 0.5 to about 5, ethylene oxide groups. The C₆ -C₁₈ alcohol itselfis preferable commercially available. C₁₂ -C₁₅ alkyl sulfate which hasbeen ethoxylated with from about 1 to about 5 moles of ethylene oxideper molecule is preferred. Where the compositions of the invention areformulated to have a pH of between 6.5 to 9.3, preferably between 8.0 to9, wherein the pH is defined herein to be the pH of a 1% solution of thecomposition measured at 20° C., surprisingly robust soil removal,particularly proteolytic soil removal, is obtained when C₁₀ -C₁₈ alkylethoxysulfate surfactant, with an average degree of ethoxylation of from0.5 to 5 is incorporated into the composition in combination with aproteolytic enzyme, such as neutral or alkaline proteases at a level ofactive enzyme of from 0.005% to 2%. Preferred alkyl(polyethoxy)sulfatesurfactants for inclusion in the present invention are the C₁₂ -C₁₅alkyl ethoxysulfate surfactants with an average degree of ethoxylationof from 1 to 5, preferably 2 to 4, most preferably 3.

Conventional base-catalyzed ethoxylation processes to produce an averagedegree of ethoxylation of 12 result in a distribution of individualethoxylates ranging from 1 to 15 ethoxy groups per mole of alcohol, sothat the desired average can be obtained in a variety of ways. Blendscan be made of material having different degrees of ethoxylation and/ordifferent ethoxylate distributions arising from the specificethoxylation techniques employed and subsequent processing steps such asdistillation.

Alkyl(polyethoxy)carboxylates suitable for use herein include those withthe formula RO(CH₂ CH₂ O)x CH₂ COO--M⁺ wherein R is a C₆ to C₂₅ alkylgroup, x ranges from 0 to 10, preferably chosen from alkali metal,alkaline earth metal, ammonium, mono-, di-, and tri-ethanol-ammonium,most preferably from sodium, potassium, ammonium and mixtures thereofwith magnesium ions. The preferred alkyl(polyethoxy)carboxylates arethose where R is a C₁₂ to C₁₈ alkyl group.

Highly preferred anionic cosurfactants herein are sodium or potassiumsalt-forms for which the corresponding calcium salt form has a low Krafttemperature, e.g., 30° C. or below, or, even better, 20° C. or lower.Examples of such highly preferred anionic cosurfactants are thealkyl(polyethoxy)sulfates.

Detersive Enzymes (including enzyme adjuncts)

Enzymes included in the present detergent compositions for a variety ofpurposes, including removal of protein-based, carbohydrate-based, ortriglyceride-based stains from surfaces such as textiles or dishes, forthe prevention of refugee dye transfer, for example in laundering, andfor fabric restoration. Suitable enzymes include proteases, amylases,lipases, cellulases, peroxidases, and mixtures thereof of any suitableorigin, such as vegetable, animal, bacterial, fungal and yeast origin.Preferred selections are influenced by factors such as pH-activityand/or stability optima, thermostability, and stability to activedetergents, builders and the like. In this respect bacterial or fungalenzymes ar e preferred, such as bacterial amylases and proteases, andfungal cellulases.

"Detersiveenzyme", as used herein, means any enzyme having a cleaning,stain removing or otherwise beneficial effect in an ADD, laundry, hardsurface cleaning or personal care detergent composition. Preferreddetersive enzymes are hydrolases such as proteases, amylases andlipases. Preferred enzymes for laundry purposes include, but are notlimited to, proteases, cellulases, lipases and peroxidases. Highlypreferred for automatic dishwashing are amylases and/or proteases,including both current commercially available types and improved typeswhich, though more and more bleach compatible though successiveimprovements, have a remaining degree of bleach deactivationsusceptibility.

Enzymes are normally incorporated into detergent or detergent additivecompositions at levels sufficient to provide a "cleaning-effectiveamount" The term "cleaning effective amount" refers to any amountcapable of producing a cleaning, stain removal, soil removal, whitening,deodorizing, or freshness improving effect on substrates such asfabrics, dishware and the like. In practical terms for currentcommercial preparations, typical amounts are up to about 5 mg by weight,more typically 0.01 mg to 3 mg, of active enzyme per gram of thedetergent composition. Stated otherwise, the finished detergentcompositions herein will typically comprise from 0.001% to 5%,preferably 0.01%-1% by weight of a commercial enzyme preparation.Accordingly, the composite particles herein will comprise from about0.1% to about 15%, preferably from about 1% to about 10%, by weight ofenzyme. Protease enzymes are usually present in such commercialpreparations at levels sufficient to provide from 0.005 to 0.1 by Ansonunits (AU) of activity per gram of composition. For certain detergents,such as in automatic dishwashing, it may be desirable to increase theactive enzyme content of the commercial preparation in order to minimizethe total amount of non-catalytically active materials and therebyimprove spotting/filming or other end-results.

Higher active levels may also be desirable in highly concentrateddetergent formulations.

Suitable examples of proteases are the subtilisins which are obtainedfrom particular strains of B. subtilis and B. licheniformis. Onesuitable protease is obtained from a strain of Bacillus, having maximumactivity throughout the pH range of 8-12, developed and sold asESPERASE® by Novo Industries A/S of Denmark, hereinafter "Novo". Thepreparation of this enzyme and analogous enzymes is described in GB1,243,784 to Novo. Other suitable proteases include ALCALASE® andSAVINASE® from Novo and MAXATASE® from International Bio-Synthetics,Inc., The Netherlands; as well as Protease A as disclosed in EP 130,756A, Jan. 9, 1985 and Protease B as disclosed in EP 303,761 A, Apr. 28,1987 and EP 130,756 A, Jan. 9, 1985. See also a high pH protease fromBacillus sp. NCIMB 40338 described in WO 9318140 A to Novo. Enzymaticdetergents comprising protease, one or more other enzymes, and areversible protease inhibitor are described in WO 9203529 A to Novo.Other preferred proteases include those of WO 9510591 A to Procter &Gamble. When desired, a protease having decreased adsorption andincreased hydrolysis is available as described in WO 9507791 to Procter& Gamble. A recombinant trypsin-like protease for detergents suitableherein is described in WO 9425583 to Novo.

In more detail, an especially preferred protease, referred to as"Protease D" is a carbonyl hydrolase variant having an amino acidsequence not found in nature, which is derived from a precursor carbonylhydrolase by substituting a different amino acid for a plurality ofamino acid residues at a position in said carbonyl hydrolase equivalentto position +76, preferably also in combination with one or more aminoacid residue positions equivalent to those selected from the groupconsisting of +99, +101, +103, +104, +107, +123, +27, +105, +109, +126,+128, +135, +156, +166, +195, +197, +204, +206, +210, +216, +217, +218,+222, +260, +265, and/or +274 according to the numbering of Bacillusamyloliquefaciens subtilisin, as described in the patent applications ofA. Baeck, et al, entitled "Protease-Containing Cleaning Compositions"having U.S. Ser. No. 08/322,676, and C. Ghosh, et al, "BleachingCompositions Comprising Protease Enzymes" having U.S. Ser. No.08/322,677, both filed Oct. 13, 1994.

Amylases suitable herein, especially for, but not limited to automaticdishwashing purposes, include, for example, x-amylases described in GB1,296,839 to Novo; RAPIDASE®, International Bio-Synthetics, Inc. andTERMAMYL®, Novo. FUNGAMYL® from Novo is especially useful. Engineeringof enzymes for improved stability, e.g., oxidative stability, is known.See, for example J. Biological Chem., Vol. 260, No. 11, June 1985, pp6518-6521. Certain preferred embodiments of the present compositions canmake use of amylases having improved stability in detergents such asautomatic dishwashing types, especially improved oxidative stability asmeasured against a reference-point of TERMAMYL® in commercial use in1993. These preferred amylases herein share the characteristic of being"stability-enhanced" amylases, characterized, at a minimum, by ameasurable improvement in one or more of: oxidative stability, e.g., tohydrogen peroxide/tetraacetylethylenediamine in buffered solution at pH9-10; thermal stability, e.g., at common wash temperatures such as about60° C.; or alkaline stability, e.g., at a pH from about 8 to about 11,measured versus the above-identified reference-point amylase. Stabilitycan be measured using any of the art-disclosed technical tests. See, forexample, references disclosed in WO 9402597. Stability-enhanced amylasescan be obtained from Novo or from Genencor International. One class ofhighly preferred amylases herein have the commonality of being derivedusing site-directed mutagenesis from one or more of the Baccillusamylases, especially the Bacillus α-amylases, regardless of whether one,two or multiple amylase strains are the immediate precursors. Oxidativestability-enhanced amylases vs. the above-identified reference amylaseare preferred for use, especially in bleaching, more preferably oxygenbleaching, as distinct from chlorine bleaching, detergent compositionsherein. Such preferred amylases include (a) an amylase according to thehereinbefore incorporated WO 9402597, Novo, Feb. 3, 1994, as furtherillustrated by a mutant in which substitution is made, using alanine orthreonine, preferably threonine, of the methionine residue located inposition 197 of the B. licheniformis alpha-amylase, known as TERMAMYL®,or the homologous position variation of a similar parent amylase, suchas B. amyloliquefaciens, B. subtilis, or B. stearothermophilus; (b)stability-enhanced amylases as described by Genencor Internatonal in apaper entitled "Oxidatively Resistant alpha-Amylases" presented at the207th American Chemical Society National Meeting, Mar. 13-17, 1994, byC. Mitchinson. Therein it was noted that bleaches in automaticdishwashing detergents inactivate alpha-amylases but that improvedoxidative stability amylases have been made by Genencor from B.licheniformis NCIB8061. Methionine (Met) was identified as th e mostlikely residue to be modified. Met was substituted, one at a time, inpositions 8, 15, 197, 256, 304, 366 and 438 leading to specific mutants,particularly important being, M197L and M197T with the M197T variantbeing the most stable expressed variant. Stability was measured inCASCADE® and SUNLIGHT®; (c) particularly preferred amylases hereininclude amylase variants having additional modification in the immediateparent as described in WO 9510603 A and are available from Novo asDURAMYL®. Other particularly preferred oxidative stability enhancedamylase include those described in WO 9418314 to Genencor Internationaland WO 9402597 to Novo. Any other oxidative stability-enhanced amylasecan be used, for example as derived by site-directed mutagenesis fromknown chimeric, hybrid or simple mutant parent forms of availableamylases. Other preferred enzyme modifications are accessible. See WO9509909 A to Novo.

Cellulases usable herein include both bacterial and fungal types,preferably having a pH optimum between 5 and 9.5. U.S. Pat. No.4,435,307, Barbesgoard et al, Mar. 6, 1984, discloses suitable fungalcellulases from Humicola insolens or Humicola strain DSM1800 or acellulase 212-producing fungus belonging to the genus Aeromonas, andcellulase extracted from the hepatopancreas of a marine mollusk,Dolabella Auricula Solander. Suitable cellulases are also disclosed inGB-A-2.075.028; GB-A-2.095.275 and DE-OS-2.247.832. CAREZYME® (Novo) isespecially useful. See also WO 9117243 to Novo.

Suitable lipase enzymes for detergent usage include those produced bymicroorganisms of the Pseudomonas group, such as Pseudomonas stutzeriATCC 19.154, as disclosed in GB 1,372,034. See also lipases in JapanesePatent Application 53,20487, laid open Feb. 24, 1978. This lipase isavailable from Amano Pharmaceutical Co. Ltd., Nagoya, Japan, under thetrade name Lipase P "Amano" or "Amano-P." Other suitable commerciallipases include Amano-CES, lipases ex Chromobacter viscosumit, e.g.Chromobacter viscosum var. lipolyticum NRRLB 3673 from Toyo Jozo Co.,Tagata, Japan; Chromobacter viscosum lipases from U.S. BiochemicalCorp., U.S.A. and Disoynth Co., The Netherlands, and lipases exPseudomonas gladioli. LIPOLASE® enzyme derived from Humicola lanuginosaand commercially available from Novo, see also EP 341,947, is apreferred lipase for use herein. Lipase and amylase variants stabilizedagainst peroxidase enzymes are described in WO 9414951 A to N ovo. Seealso WO 920524 9 and RD 94359044.

Cutinase enzymes suitable for use herein are described in WO 8809367 Ato Genencor.

Peroxidase enzymes may be used in combination with oxygen sources, e.g.,percarbonate, perborate, hydrogen peroxide, etc., for "solutionbleaching" or prevention of transfer of dyes or pigments removed fromsubstrates during the wash to other substrates present in the washsolution. Known peroxidases include horseradish peroxidase, ligninase,and haloperoxidases such as chloro- or bromo-peroxidase.Peroxidase-containing detergent compositions are disclosed in WO89099813 A, Oct. 19, 1989 to Novo and WO 8909813 A to Novo.

A range of enzyme materials and means for their incorporation intosynthetic detergent compositions is also disclosed in WO 9307263 A andWO 9307260 A to Genencor International, WO 8908694 A to Novo, and U.S.Pat. No. 3,553,139, Jan. 5, 1971 to McCarty et al. Enzymes are furtherdisclosed in U.S. Pat. No. 4,101,457, Place et al, Jul. 18, 1978, and inU.S. Pat. No. 4,507,219, Hughes, Mar. 26, 1985. Enzyme materials usefulfor liquid detergent formulations, and their incorporation into suchformulations, are disclosed in U.S. Pat. No. 4,261,868, Hora et al, Apr.14, 1981. Enzymes for use in detergents can be stabilised by varioustechniques. Enzyme stabilisation techniques are disclosed andexemplified in U.S. Pat. No. 3,600,319, Aug. 17, 1971, Gedge et al, EP199,405 and EP 200,586, Oct. 29, 1986, Venegas. Enzyme stabilisationsystems are also described, for example, in U.S. Pat. No. 3,519,570. Auseful Bacillus, sp. AC13 giving proteases, xylanases and cellulases, isdescribed in WO 9401532 A to Novo.

Enzyme Stabilizing System

The enzyme-containing composite particles and/or overall detergentcompositions herein may comprise from about 0.001% to about 20%,preferably from about 0.005% to about 8%, most preferably from about0.01% to about 6%, by weight of an enzyme stabilizing system. The enzymestabilizing sys tem can be any stabilizing system which is compatiblewith the detersive enzyme. Such a system may be inherently provided byother formulation actives, or be added separately, e.g., by theformulator or by a manufacturer of detergent-ready enzymes. Suchstabilizing systems can, for example, comprise calcium ion, boric acid,propylene glycol, short chain carboxylic acids, boronic acids, andmixtures thereof, and are designed to address different stabilizationproblems depending on the type of enzyme and type of detergentcomposition.

One stabilizing approach is the use of water-soluble sources of calciumand/or magnesium ions in the composite particles or in the finishedcompositions which provide such ions to the enzymes. Calcium ions aregenerally more effective than magnesium ions and are preferred herein ifonly one type of cation is being used. Enzymatic detergent compositionsmay comprise from about 1 to about 30, preferably from about 2 to about20, more preferably from about 8 to about 12 millimoles of calcium ionper kg of finished detergent composition, though variation is possibledepending on factors including the multiplicity, type a nd levels ofenzymes incorporated. Preferably water-soluble calcium or magnesiumsalts are employed, including for example calcium chloride, calciumhydroxide, calcium formate, calcium malate, calcium maleate, calciumhydroxide and calcium acetate; more generally, calcium sulfate ormagnesium salts corresponding to the exemplified calcium salts may beused. Further increased levels of calcium and/or magnesium may of coursebe useful, for example for promoting the grease-cutting action ofcertain types of surfactant.

Another stabilizing approach is by use of borate species. See Severson,U.S. Pat. No. 4,537,706. Borate stabilizers, when used, may be at levelsof up to 10% or more of the composite particles or the finishedcomposition, though more typically levels of up to about 3% by weight ofboric acid or other borate compounds such as borax or orthoborate areused. Substituted boric acids such as phenylboronic acid, butaneboronicacid, p-bromophenylboronic acid or the like can be used in place ofboric acid and reduced levels of total boron in detergent compositionsmay be possible though the use of such substituted boron derivatives.

Stabilizing systems of certain cleaning compositions, for example ADD's,may further comprise from 0 to about 10%, preferably from about 0.01% toabout 6% by weight, of chlorine bleach scavengers, added to preventchlorine bleach species present in many water supplies from attackingand inactivating the enzymes, especially under alkaline conditions.While chlorine levels in water may be small, typically in the range fromabout 0.5 ppm to about 1.75 ppm, the available chlorine in the totalvolume of water that comes in contact with the enzyme, for exampleduring dish- or fabric-washing, can be relatively large; accordingly,enzyme stability to chlorine in-use is sometimes problematic. Sinceperborate or percarbonate, which have the ability to react with chlorinebleach, may be present in certain of the instant compositions in amountsaccounted for separately from the stabilizing system, the use ofadditional stabilizers against chlorine, may, most generally, not beessential, though improved results may be obtainable from their use.Suitable chlorine scavenger anions are widely known and readilyavailable, and, if used, can be salts containing ammonium cations withsulfite, bisulfite, thiosulfite, thiosulfate, iodide, etc. Antioxidantssuch as carbamate, ascorbate, etc., organic amines such asethylenediaminetetracetic acid (EDTA) or alkali metal salt thereof,monoethanolamine (MEA), and mixtures thereof can likewise be used.Likewise, special enzyme inhibition systems can be incorporated suchthat different enzymes have maximum compatibility. Other conventionalscavengers such as bisulfate, nitrate, chloride, sources of hydrogenperoxide such as sodium perborate tetrahydrate, sodium perboratemonohydrate and sodium percarbonate, as well as phosphate, condensedphosphate, acetate, benzoate, citrate, formate, lactate, malate,tartrate, salicylate, etc., and mixtures thereof can be used if desired.In general, since the chlorine scavenger function can be performed byingredients separately listed under better recognized functions, (e.g.,hydrogen peroxide sources), there is no absolute requirement to add aseparate chlorine scavenger unless a compound performing that functionto the desired extent is absent from an enzyme-containing embodiment ofthe invention; even then, the scavenger is added only for optimumresults. Moreover, the formulator will exercise a chemist's normal skillin avoiding the use of any enzyme scavenger or stabilizer which ismajorly incompatible, as formulated, with other reactive ingredients, ifused. In relation to the use of ammonium salts, such salts can be simplyadmixed with the detergent composition but are prone to adsorb waterand/or liberate ammonia during storage. Accordingly, such materials, ifpresent, are desirably protected in a particle such as that described inU.S. Pat. No. 4,652,392, Baginski et al.

Silicone and Phosphate Ester Suds Suppressors

The detergent compositions optionally contain an alkyl phosphate estersuds suppressor, a silicone suds suppressor, or combinations thereof.Levels in general are from 0% to about 10%, preferably, from about0.001% to about 5%. Typical levels tend to be low, e.g., from about0.01% to about 3% when a silicone suds suppressor is used. Preferrednon-phosphate compositions omit the phosphate ester component entirely.

Silicone suds suppressor technology and other defoaming agents usefulherein are extensively documented in "Defoaming, Theory and IndustrialApplications", Ed., P. R. Garrett, Marcel Dekker, N.Y., 1973, ISBN0-8247-8770-6, incorporated herein by reference. See especially thechapters entitled "Foam control in Detergent Products" (Ferch et al) and"Surfactant Antifoams" (Blease et al). See also U.S. Pat. Nos. 3,933,672and 4,136,045. Highly preferred silicone suds suppressors are thecompounded types known for use in laundry detergents such as heavy-dutygranules, although types hitherto used only in heavy-duty liquiddetergents may also be incorporated in the instant compositions. Forexample, polydimethylsiloxanes having trimethylsilyl or alternateendblocking units may be used as the silicone. These may be compoundedwith silica and/or with surface-active nonsilicon components, asillustrated by a suds suppressor comprising 12% silicone/silica, 18%stearyl alcohol and 70% starch in granular form. A suitable commercialsource of the silicone active compounds is Dow Corning Corp.

Levels of the suds suppressor depend to some extent on the sudsingtendency of the composition, for example, an detergent composition foruse at 2000 ppm comprising 2% octadecyldimethylamine oxide may notrequire the presence of a suds suppressor. Indeed, it is an advantage ofthe present invention to select cleaning-effective amine oxides whichare inherently much lower in foam-forming tendencies than the typicalcoco amine oxides. In contrast, formulations in which amine oxide iscombined with a high-foaming anionic cosurfactant, e.g., alkyl ethoxysulfate, benefit greatly from the presence of suds suppressors.

Phosphate esters have also been asserted to provide some protection ofsilver and silver-plated utensil surfaces, however, the instantcompositions can have excellent silverware without a phosphate estercomponent. Without being limited by theory, it is believed that lower pHformulations, e.g., those having pH of 9.5 and below, plus the presenceof the essential amine oxide, both contribute to improved silver care.

If it is desired nonetheless to use a phosphate ester, suitablecompounds are disclosed in U.S. Pat. No. 3,314,891, issued Apr. 18,1967, to Schmolka et al, incorporated herein by reference. Preferredalkyl phosphate esters contain from 16-20 carbon atoms. Highly preferredalkyl phosphate esters are monostearyl acid phosphate or monooleyl acidphosphate, or salts thereof, particularly alkali metal salts, ormixtures thereof.

It has been found preferable to avoid the use of simplecalcium-precipitating soaps as antifoams in the present compositions asthey tend to deposit on the dishware. Indeed, phosphate esters are notentirely free of such problems and the formulator will generally chooseto minimize the content of potentially depositing antifoams in theinstant compositions.

Corrosion Inhibitor

The detergent compositions may contain a corrosion inhibitor. Suchcorrosion inhibitors are preferred components of automatic dishwashingcompositions in accord with the invention, and are preferablyincorporated at a level of from 0.05% to 10%, preferably from 0.1% to 5%by weight of the total composition.

Suitable corrosion inhibitors include paraffin oil typically apredominantly branched aliphatic hydrocarbon having a number of carbonatoms in the range of from 20 to 50: preferred paraffin oil selectedfrom predominantly branched C₂₅₋₄₅ species with a ratio of cyclic tononcyclic hydrocarbons of about 32:68; a paraffin oil meeting thesecharacteristics is sold by Wintershall, Salzbergen, Germany, under thetrade name WINOG 70.

Other suitable corrosion inhibitor compounds include benzotriazole andany derivatives thereof, mercaptans and diols, especially mercaptanswith 4 to 20 carbon atoms including lauryl mercaptan, thiophenol,thionaphthol, thionalide and thioanthranol. Also suitable are the C₁₂-C₂₀ fatty acids, or their salts, especially aluminum tristearate. TheC₁₂ -C₂₀ hydroxy fatty acids, or their salts, are also suitable.Phosphonated octa-decane and other anti-oxidants such asbetahydroxytoluene (BHT) are also suitable. Bismuth nitrate is alsosuitable.

Dispersant polymers

A dispersant polymer may optionally be used in the instant detergentcompositions in the range from 0% to about 25%, preferably from about0.5% to about 20%, more preferably from about 1% to about 7% by weightof the overall composition. Dispersant polymers are also useful forimproved filming performance of the present ADD compositions, especiallyin higher pH embodiments, such as those in which wash pH exceeds about9.5. Particularly preferred are polymers which inhibit the deposition ofcalcium carbonate or magnesium silicate on dishware.

Dispersant polymers suitable for use herein are illustrated by thefilm-forming polymers described in U.S. Pat. No. 4,379,080 (Murphy),issued Apr. 5, 1983, incorporated herein by reference.

Suitable polymers are preferably at least partially neutralized oralkali metal, ammonium or substituted ammonium (e.g., mono-, di- ortriethanolammonium) salts of polycarboxylic acids. The alkali metal,especially sodium salts are most preferred. While the molecular weightof the polymer can vary over a wide range, it preferably is from about1000 to about 500,000, more preferably is from about 1000 to about250,000, and most preferably, especially if the detergent composition isfor use in North American automatic dishwashing appliances, is fromabout 1000 to about 10,000.

Other suitable dispersant polymers include those disclosed in U.S. Pat.No. 3,308,067 issued Mar. 7, 1967, to Diehl, incorporated herein byreference. Unsaturated monomeric acids that can be polymerized to formsuitable dispersant polymers include acrylic acid, maleic acid (ormaleic anhydride), fumaric acid, itaconic acid, aconitic acid, mesaconicacid, citraconic acid and methylenemalonic acid. The presence ofmonomeric segments containing no carboxylate radicals such as methylvinyl ether, styrene, ethylene, etc. is suitable provided that suchsegments do not constitute more than about 50% by weight of thedispersant polymer.

Copolymers of acrylamide and acrylate having a molecular weight of fromabout 3,000 to about 100,000, preferably from about 4,000 to about20,000, and an acrylamide content of less than about 50%, preferablyless than about 20%, by weight of the dispersant polymer can also beused. Most preferably, such dispersant polymer has a molecular weight offrom about 4,000 to about 20,000 and an acrylamide content of from about0% to about 15%, by weight of the polymer.

Particularly preferred dispersant polymers are low molecular weightmodified polyacrylate copolymers. Such copolymers contain as monomerunits: a) from about 90% to about 10%, preferably from about 80% toabout 20% by weight acrylic acid or its salts and b) from about 10% toabout 90%, preferably from about 20% to about 80% by weight of asubstituted acrylic monomer or its salt and have the general formula:--[(C(R²)C(R¹)(C(O)OR³)]-- wherein the incomplete valences inside thesquare braces are hydrogen and at least one of the substituents R¹, R²or R³, preferably R¹ or R², is a 1 to 4 carbon alkyl or hydroxyalkylgroup, R¹ or R² can be a hydrogen and R³ can be a hydrogen or alkalimetal salt. Most preferred is a substituted acrylic monomer wherein R¹is methyl, R² is hydrogen and R³ is sodium.

The low molecular weight polyacrylate dispersant polymer preferably hasa molecular weight of less than about 15,000, preferably from about 500to about 10,000, most preferably from about 1,000 to about 5,000. Themost preferred polyacrylate copolymer for use herein has a molecularweight of 3500 and is the fully neutralized form of the polymercomprising about 70% by weight acrylic acid and about 30% by weightmethacrylic acid.

Other suitable modified polyacrylate copolymers include the lowmolecular weight copolymers of unsaturated aliphatic carboxylic acidsdisclosed in U.S. Pat. Nos. 4,530,766, and 5,084,535, both incorporatedherein by reference.

Other dispersant polymers useful herein include the polyethylene glycolsand polypropylene glycols having a molecular weight of from about 950 toabout 30,000 which can be obtained from the Dow Chemical Company ofMidland, Michigan. Such compounds for example, having a melting pointwithin the range of from about 30° to about 100° C. can be obtained atmolecular weights of 1450, 3400, 4500, 6000, 7400, 9500, and 20,000.Such compounds are formed by the polymerization of ethylene glycol orpropylene glycol with the requisite number of moles of ethylene orpropylene oxide to provide the desired molecular weight and meltingpoint of the respective polyethylene glycol and polypropylene glycol.The polyethylene, polypropylene and mixed glycols are referred to usingthe formula HO(CH₂ CH₂ O)_(m) (CH₂ CH(CH₃)O)_(n) (CH(CH₃)CH₂ O)OHwherein m, n, and o are integers satisfying the molecular weight andtemperature requirements given above.

Yet other dispersant polymers useful herein include the cellulosesulfate esters such as cellulose acetate sulfate, cellulose sulfate,hydroxyethyl cellulose sulfate, methylcellulose sulfate, andhydroxypropylcellulose sulfate. Sodium cellulose sulfate is the mostpreferred polymer of this group.

Other suitable dispersant polymers are the carboxylated polysaccharides,particularly starches, celluloses and alginates, described in U.S. Pat.No. 3,723,322, Diehl, issued Mar. 27, 1973; the dextrin esters ofpolycarboxylic acids disclosed in U.S. Pat. No. 3,929,107, Thompson,issued Nov. 11, 1975; the hydroxyalkyl starch ethers, starch esters,oxidized starches, dextrins and starch hydrolysates described in U.S.Pat. No. 3,803,285, Jensen, issued Apr. 9, 1974; the carboxylatedstarches described in U.S. Pat. No. 3,629,121, Eldib, issued Dec. 21,1971; and the dextrin starches described in U.S. Pat. No. 4,141,841,McDanald, issued Feb. 27, 1979; all incorporated herein by reference.Preferred cellulose-derived dispersant polymers are the carboxymethylcelluloses.

Yet another group of acceptable dispersants are the organic dispersantpolymers, such as polyaspartate.

Other Optional Adjuncts

Depending on whether a greater or lesser degree of compactness isrequired, filler materials can also be present in the detergentcompositions. These include sucrose, sucrose esters, sodium chloride,sodium sulfate, potassium chloride, potassium sulfate, etc., in amountsup to about 70%, preferably from 0% to about 40% of the detergentcomposition. A preferred filler is sodium sulfate, especially in goodgrades having low levels of trace impurities.

Sodium sulfate used herein preferably has a purity sufficient to ensureit is non-reactive with bleach; it may also be treated with low levelsof sequestrants, such as phosphonates in magnesium-salt form. Note thatpreferences, in terms of purity sufficient to avoid decomposing bleach,applies also to builder ingredients.

Hydrotrope materials such as sodium benzene sulfonate, sodium toluenesulfonate, sodium cumene sulfonate, etc., can be present in minoramounts.

Bleach-stable perfumes (stable as to odor); and bleach-stable dyes (suchas those disclosed in U.S. Pat. No. 4,714,562, Roselle et al, issuedDec. 22, 1987); can also be added to the present compositions inappropriate amounts. Other common detergent ingredients are notexcluded.

Since certain detergent compositions herein can contain water-sensitiveingredients, e.g., in embodiments comprising anhydrous amine oxides oranhydrous citric acid, it is desirable to keep the free moisture contentof the detergent compositions at a minimum, e.g., 7% or less, preferably4% or less of the detergent composition; and to provide packaging whichis substantially impermeable to water and carbon dioxide. Plasticbottles, including refillable or recyclable types, as well asconventional barrier cartons or boxes are generally suitable. Wheningredients are not highly compatible, e.g., mixtures of silicates andcitric acid, it may further be desirable to coat at least one suchingredient with a low-foaming nonionic surfactant for protection. Thereare numerous waxy materials which can readily be used to form suitablecoated particles of any such otherwise incompatible components.

Method for Cleaning

The detergent compositions herein may be utilized in methods forcleaning soiled tableware and laundry.

A preferred method for cleaning soiled tableware comprises contactingthe tableware with a pH wash aqueous medium of at least 8. The aqueousmedium preferably comprises at least about 0.1 ppm bleach catalyst andavailable oxygen from a peroxygen bleach.

A preferred method for cleaning soiled tableware comprises using thecatalyst/enzyme-containing particles, low foaming surfactant anddetergency builder. The aqueous medium is formed by dissolving asolid-form automatic dishwashing detergent in an automatic dishwashingmachine. A particularly preferred method also includes low levels ofsilicate, preferably from about 3% to about 10% SiO₂.

EXAMPLE 1

3,240 g gelatine (Bloom strength O) and 3,240 g sugar were added to a10% by weight solution of metal-containing bleach catalyst in 5,200 gwater while stirring. Subsequently, 650 g coconut oil was emulsified inthe solution thus obtained.

The dry matter content of the mixture thus prepared was about 60%, about16% being metal-containing bleach catalyst and the viscosity was 96 cpat 55° C.

The mixture was spray-dried in a spray drying tower while simultaneouslyintroducing corn starch therein as a powdering composition.

The mixture was introduced at a rate of 2 l/min. and the temperature ofthe spray drying zone was about 70° C.

The final product (about 9,200 g) was sieved and the mesh 30-mesh 120(ASTM) fraction was collected and analyzed. The collected fractioncontained 14.1% metal-containing bleach catalyst and the averageparticle diameter was about 350 micrometer.

EXAMPLE 2

2,388 g gelatine was dissolved in 2,135 g water by stirring and heatingto a temperature of about 60° C. A solution of 126 g sodium hydroxide in215 g water was added under stirring to the gelatine solution at atemperature of 60° C. After stirring for 20 min. at 60° C. 135 gconcentrated sulfuric acid (96%) was added and the pH-value was adjustedat about 5.5. 900 g of the solution thus obtained ("hydrolyzedgelatine") was mixed with a solution of 100 g metal-containing bleachcatalyst in 1,150 g water, 450 spray-dried glucose syrup ("Monsweet R1924) and 50 g coconut oil while stirring at 55° C. When the coconut hadbeen emulsified in the aqueous medium an additional amount of 700 gwater was added. The dry matter content of the mixture thus obtained wasabout 30%, about 10% being metal-containing bleach catalyst. Theviscosity of the mixture was about 50 cp at 600C. The mixture wasspray-dried in a conventional spray-drying tower at an inlet temperatureof 240° C. and an outlet temperature of 97° C.

The spray-dried product (about 900 g) was sieved and the sieve fractionhaving a particle size of less than 100 mesh (ASTM) was collected.

This fraction contained 9.7% metal-containing bleach catalyst and theaverage particle size was about 50 micrometer.

EXAMPLE 3

1060 g gum arabic and 1010 g sugar (saccharose) were added to a solutionof 1375 g metal-containing bleach catalyst in 1850 g water whilestirring. 138 g coconut oil was emulsified in the solution thusobtained.

The dry matter content of the mixture thus prepared was about 45%, about11.4% being metal-containing bleach catalyst and the viscosity was 108cP at 57° C.

The mixture was spray-dried in a spray drying tower while simultaneouslyintroducing corn starch therein as a powdering composition.

The mixture was introduced at a rate of 1.5 l/min. and the temperatureof the spray drying zone was about 65° C.

The final product (about 3500 g) was sieved and the mesh 30-mesh 170(ASTM) fraction was collected and analysed.

The collected fraction contained 8.2% metal-containing bleach catalystand the average particle diameter was about 250 micrometers.

In the compositions, the abbreviated component identifications have thefollowing meanings:

    ______________________________________                                        Nonionic   C.sub.13 -C.sub.15 mixed ethoxylated/propoxylated fatty                       alcohol with an average degree of ethoxylation                                of 3.8 and an average degree of propoxylation                                 of 4.5 sold under the tradename Plurafac                                      LF404 by BASF GmbH (low foaming)                                   Metasilicate                                                                             Sodium metasilicate (SiO.sub.2 :Na.sub.2 O ratio = 1.0)            Silicate   Amorphous Sodium Silicate (SiO.sub.2 :Na.sub.2 O ratio =                      2.0)                                                               Carbonate  Anhydrous sodium carbonate                                         Phosphate  Sodium tripolyphosphate                                            480N       Random copolymer of 3:7 acrylic/methacrylic                                   acid, average molecular weight about 3,500                         Citrate    Tri-sodium citrate dihydrate                                       PB1        Anhydrous sodium perborate monohydrate                             TAED       Tetraacetyl ethylene diamine                                       Cationic precursor                                                                       Cationic peroxyacid bleach precursor salt of                                  trialkyl ammonium methylene C.sub.5 -alkyl                                    caprolactam with tosylate                                          BzP        Dibenzoyl peroxide                                                 DETPMP     Diethylene triamine penta (methylene                                          phosphonic acid), marketed by Monsanto under                                  the tradename Dequest 2060                                         HEDP       Ethane 1-hydroxy-1,1-diphosphonic acid                             Bismuth nitrate                                                                          Bismuth nitrate salt                                               Bismuth (HEDP)                                                                           Complex of bismuth and HEDP                                        Paraffin   Paraffin oil sold under the tradename Winog 70                                by Wintershall.                                                    BD/MA      Copolymer of butadiene/maleic acid as sold by                                 Polysciences inc under the tradename reference                                no. 07787                                                          Protease   Proteolytic enzyme sold under the tradename                                   Savinase by Novo Industries A/S (approx 2%                                    enzyme activity).                                                  Amylase    Amylolytic enzyme sold under the tradename                                    Termamyl 60T by Novo Industries A/S (approx                                   0.9% enzyme activity)                                              BSA        Amylolytic enzyme sold under the tradename                                    LE17 by Novo Industries A/S (approx 1%                                        enzyme activity)                                                   Sulphate   Anhydrous sodium sulphate.                                         pH         Measured as a 1% solution in distilled water at                               20° C.                                                      ______________________________________                                    

In the following examples all levels of enzyme quoted are expressed as %active enzyme by weight of the composition.

EXAMPLE 1

The following bleach-containing machine dishwashing compositions wereprepared (parts by weight). Compositions A is a comparative composition,compositions B to G are in accord with the invention.

    ______________________________________                                                  A    B      C      D    E    F    G                                 ______________________________________                                        Citrate     15.0   15.0   15.0 15.0 15.0 15.0 --                              480N        6.0    6.0    6.0  6.0  6.0  6.0  --                              Carbonate   17.5   17.5   17.5 17.5 17.5 17.5 --                              Phosphate   --     --     --   --   --   --   38.0                            Silicate (as SiO.sub.2)                                                                   8.0    8.0    8.0  8.0  8.0  8.0  14.0                            Metasilicate                                                                              1.2    1.2    1.2  1.2  1.2  1.2  2.5                             (as SiO.sub.2)                                                                PB1 (AvO)   1.2    1.2    1.5  1.5  1.5  2.2  1.2                             Bleach catalyst                                                                           --     0.2    0.1  0.05 0.1  0.2  0.3                             encapsulate                                                                   particle - formula                                                            given below                                                                   TAED        2.2    2.2    2.2  --   --   2.2  2.2                             BzP         --     --     --   0.8  --   --   --                              Cationic    --     --     --   --   3.3  --   --                              precursor                                                                     Paraffin    0.5    0.5    0.5  0.5  0.5  0.5  0.5                             Bismuth     --     0.2    0.2  0.2  0.3  0.4  0.2                             nitrate                                                                       BD/MA       --     --     --   --   --   --   0.5                             Protease    0.04   0.04   0.04 0.04 0.04 0.04 0.04                            Amylase     0.03   0.03   0.03 0.03 0.03 0.03 --                              BSA         --     --     --   --   --   --   0.03                            DETPMP      0.13   0.13   0.13 0.13 0.13 0.13 --                              HEDP        1.0    1.0    1.0  1.0  1.0  1.0  --                              Nonionic    2.0    2.0    2.0  2.0  2.0  2.0  1.5                             Sulphate    23.0   22.8   22.4 22.7 22.2 21.5 0.3                             misc inc moisture                                                             to balance                                                                    pH (1% solution)                                                                          10.7   10.7   10.7 10.7 10.7 10.7 11.0                            ______________________________________                                    

Encapsulate particles containing zero-bloom gelatin at a level of 96.6%and 3.4% pentaamineacetocobalt (III) nitrate bleach catalyst. Particlesize of the encapsulates 10-450 micrometers.

What is claimed is:
 1. A composite particle for incorporation intogranular detergent compositions, said composite particle consisting ofby weight of the particle:(a) from 1% to 50% of a transitionmetal-containing bleach catalyst, selected from the group consisting ofcopper, cobalt, iron, titanium, ruthenium, tungsten, molybdenum,manganese catalysts, and mixtures thereof; (b) from 40% to 99% of anencapsulating material, selected from the group consisting of gelatine,hydrolyzed gelatine, film forming carbohydrates, and mixtures thereof;and (c) from 0.5% to 20% water.
 2. A composite particle according toclaim 1 having a particle size of from 10 micrometers to 450micrometers.
 3. A composite particle according to claim 1 wherein saidtransition metal-containing bleach catalyst is selected from tile groupconsisting of Mn^(IV) ₂ (u-O)₃(1,4,7-trimethyl-1,4,7-triazacyclononane)₂ -(PF₆)₂ ; Mn^(III) ₂(u-O)(u-OAc)₂ (1,4,7-trimethyl-1,4,7-triazacyclononane)₂ -(ClO₄)₂ ;Mn^(IV) ₄ (u-O)₆ (1,4,7-triazacyclononane)₄ -(ClO₄)₂ ; Mn^(III) Mn^(IV)₄ (u-O)(u-OAc)₂ (1,4,7-trimethiyl-1,4,7-triazacyclononane)₂ -(ClO₄)₃ ;Mn(1,4,7-trimethyl-1,4,7-triazacyclononane(OCH₃)₃ -(PF₆);Co(2,2'-bispyridylamine)Cl₂ ; trisdipyridylamine Co^(II) -perchlorate,Co-bispyridylmethane complex, Mn-bispyridylmethane complex,Co-bispyridylamine complex, Mn-bispyridylamine complex,Co(2,2'-bispyridylamine)Cl₂,Di(isothiocyanato)bispyridylamine-cobalt(II), Co(2,2'-bispyridylamine)₂O₂ ClO₄, Bis-(2,2'-bispyridylamine) copper(II) perchlorate,tris(di-2-pyridylamine) iron(II) perchlorate, Mn gluconate, Mn(CF₃SO₃)₂, [Co(NH₃)₅ Cl]Cl₂, [Co(NH₃)₅ OAc]Cl₂, [Co(NH₃)₅ OAc](OAc)₂[Co(NH₃)₅ OAc](PF₆)₂, [Co(NH₃)₅ OAc](SO₄), [Co(NH₃)₅ OAc](BF₄)₂,[Co(NH₃)₅ OAc](NO₃)₂, and mixtures thereof.
 4. A composite particleaccording to claim 1 wherein said composite particle consists of between50% and 98% of said encapsulating material.
 5. A composite particleaccording to claim 1 wherein the encapsulating material is a low-bloomgelatin.
 6. A composite particle according to claim 1 consisting of from2% to 30% by weight of the metal-containing bleach catalyst.
 7. Acomposite particle according to claim 4 wherein said composite particleconsists of between 60% and 97% of said encapsulating material.
 8. Acomposite particle according to claim 6 consisting of from 3% to 25%, byweight, of said bleach catalyst.
 9. A composite particle according toclaim 3 wherein said transition metal-containing bleach catalyst is[Co(NH₃)₅ OAc](NO₃)₂.